The traffic shift, part of the California Department of Transportation's $122.1 million I-5 North Stockton Improvement Project, will continue through the summer.

Caltrans will alternately close the left, center and right lanes on northbound I-5 from Country Club Boulevard to Hammer through Thursday from 8 p.m. to 6 a.m.

Motorists are advised to expect 15-minute delays. Alternate routes should be taken whenever possible.

The I-5 North Stockton Improvement Project will widen the freeway to eight lanes from Country Club Boulevard to Hammer Lane, as well as adding auxiliary lanes and sound walls. It will also introduce San Joaquin County's first High Occupancy Vehicle (carpool) lanes. The project is slated for completion in 2015.